Energy attenuating mounting foot for a cabin attendant seat

ABSTRACT

In various embodiments, the present disclosure provides an energy attenuating mounting foot comprising a load beam having a longitudinal axis, a top surface, a bottom surface, an inner track interface lobe, and an outer track interface lobe, the inner track interface lobe and the outer track interface lobe extending laterally from the load beam, and a channel along the longitudinal axis having a depth extending from the load beam bottom surface toward the top surface. In various embodiments, the inner track interface lobe has a first length extending in a direction from the bottom surface towards the top surface and the outer track interface lobe has a second length extending in a direction from the bottom surface towards the top surface, the first length being less than the second length.

FIELD

The present disclosure relates to restraint devices for vehicle interiorfixtures. More specifically, this disclosure described relates toimproved track fittings that attenuate the loads transmitted to a track.

BACKGROUND

To facilitate interior installation and reconfiguration, aircraft cabinfixtures may be secured to rails or tracks which typically are attachedto interior portions of the aircraft cabin. Fixtures installed on tracksmay be repositioned and locked into place along the track, thus allowingfor a great number of possible configurations to meet customer andoperator needs. A mounting member typically mates the track to theaircraft cabin fixture and transmits mechanical load between theaircraft cabin fixture and the track.

SUMMARY

In various embodiments, the present disclosure provides an energyattenuating mounting foot comprising a load beam having a longitudinalaxis, a top surface, a bottom surface, and an inner track interface lobeand an outer track interface lobe, the inner track interface lobe andthe outer track interface lobe extending laterally from the load beam,and a channel along the longitudinal axis having a depth extending fromthe load beam bottom surface toward the top surface. In variousembodiments, the inner track interface lobe has a first length extendingin a direction from the bottom surface towards the top surface and theouter track interface lobe has a second length extending in a directionfrom the bottom surface towards the top surface, the first length beingless than the second length.

In various embodiments, the inner track interface lobe and inner trackinterface lobe are shaped to fit through an opening of a track having amounting foot interface lobe. In various embodiments, the inner trackinterface lobe is separated from the mounting foot interface lobe. Invarious embodiments, the inner track interface lobe contacts themounting foot interface lobe in response to a load placed on the loadbeam. In various embodiments, the channel extends along a portion of thelongitudinal axis. In various embodiments, the mounting foot comprisesat least one of steel, aluminum, aluminum alloy, titanium, or titaniumalloy. In various embodiments, the load beam comprises a martensiticprecipitation-hardening stainless steel. In various embodiments, amaterial grain direction of the load beam substantially parallels thelongitudinal axis. In various embodiments, the load beam undergoesplastic deformation across the channel in response to a load placed onthe load beam. In various embodiments, the load beam further comprises astud. In various embodiments, the stud is coupled to a cabin fixture.

In various embodiments, the present disclosure provides an energyattenuating mounting foot comprising a load beam having a longitudinalaxis, a top surface, a bottom surface, a first inner track interfacelobe, a second inner track interface lobe, a first outer track interfacelobe and a second outer track interface lobe, the first inner trackinterface lobe, the second inner track interface lobe, the first outertrack interface lobe and the second outer track interface lobe extendinglaterally from the load beam. In various embodiments, the first innertrack interface lobe, the second inner track interface lobe, the firstouter track interface lobe and the second outer track interface lobe aredisplaced along the longitudinal axis. In various embodiments, theenergy attenuating mounting foot further comprises a channel along thelongitudinal axis terminating at the first inner track interface lobeand the second inner track interface lobe, the channel having a depthextending from the load beam bottom surface toward the top surface.

In various embodiments, the first inner track interface lobe and thesecond outer track interface lobe are shaped to fit through openings ofa track having a mounting foot interface lobe. In various embodiments,the first inner track interface lobe is separated from the mounting footinterface lobe. In various embodiments, the first inner track interfacelobe is configured to contact the mounting foot interface lobe inresponse to deformation of the load beam. In various embodiments, theload beam comprises a stud. In various embodiments, the load beamcomprises at least one of steel, aluminum, aluminum alloy, titanium, ortitanium alloy. In various embodiments, the load beam comprises amartensitic precipitation-hardening stainless steel. In variousembodiments, a material grain direction of the load beam substantiallyparallels the longitudinal axis.

In various embodiments, the present disclosure provides a method ofmanufacturing an energy attenuating mounting foot comprising forming aload beam having a longitudinal axis, a top surface, a bottom surface,and an inner track interface lobe and an outer track interface lobedisposed along the longitudinal axis of the load beam extendinglaterally from the load beam. In various embodiments, the method furthercomprises forming a channel along the longitudinal axis of the load beamin the bottom surface of the load beam to a depth between the bottomsurface and the top surface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a coupling between a seat, an energy attenuatingmounting foot, and an aircraft mounting track, in accordance withvarious embodiments;

FIGS. 2A, 2B, and 2C, illustrate a perspective of an energy attenuatingmounting foot, in accordance with various embodiments;

FIG. 2D illustrates a bottom view of an energy attenuating mounting footdetailing a channel cut into the load beam, in accordance with variousembodiments;

FIG. 2E illustrates a perspective of an energy attenuating mounting footnoting the plane of a sectional view, in accordance with variousembodiments;

FIG. 2F illustrates a vertical section perpendicular to the longitudinalaxis through an energy attenuating mounting foot, in accordance withvarious embodiments;

FIG. 3A illustrates an aircraft track, in accordance with variousembodiments;

FIG. 3B illustrates detailed features of an aircraft track, inaccordance with various embodiments;

FIG. 4A illustrates an energy attenuating mounting foot disposed in anaircraft track subjected to an upward force, in accordance with variousembodiments;

FIG. 4B illustrates an energy attenuating mounting foot disposed in anaircraft subjected to an upward force with interface lobes engaging, inaccordance with various embodiments

FIG. 4C illustrates a vertical section perpendicular to the longitudinalaxis through an energy attenuating mounting foot disposed in an aircrafttrack taken at an outer track interface lobe, in accordance with variousembodiments;

FIG. 5A illustrates an energy attenuating mounting foot disposed in anaircraft track subjected to an upward force, in accordance with variousembodiments;

FIG. 5B illustrates a vertical section perpendicular to the longitudinalaxis through an energy attenuating mounting foot disposed in an aircrafttrack taken at an inner track interface lobe, in accordance with variousembodiments;

FIG. 6 illustrates a contour plot of stresses within an energyattenuating mounting foot when exposed to 16 G dynamic loads, inaccordance with various embodiments;

FIG. 7 illustrates a contour plot of stresses within an aircraft trackcoupled to an energy attenuating mounting foot with lobes engaged whenexposed to 16 G dynamic loads, in accordance with various embodiments;and

FIG. 8 illustrates a method of manufacturing an energy attenuatingmooting foot, in accordance with various embodiments.

The subject matter of the present disclosure is particularly pointed outand distinctly claimed in the concluding portion of the specification. Amore complete understanding of the present disclosure, however, may bestbe obtained by referring to the detailed description and claims whenconsidered in connection with the drawing figures, wherein like numeralsdenote like elements.

DETAILED DESCRIPTION

The detailed description of exemplary embodiments herein makes referenceto the accompanying drawings, which show exemplary embodiments by way ofillustration. While these exemplary embodiments are described insufficient detail to enable those skilled in the art to practice thedisclosure, it should be understood that other embodiments may berealized and that logical changes and adaptations in design andconstruction may be made in accordance with this disclosure and theteachings herein without departing from the spirit and scope of thedisclosure. Thus, the detailed description herein is presented forpurposes of illustration only and not of limitation. The scope of thedisclosure is defined by the appended claims. For example, the stepsrecited in any of the method or process descriptions may be executed inany order and are not necessarily limited to the order presented.Furthermore, any reference to singular includes plural embodiments, andany reference to more than one component or step may include a singularembodiment or step. Also, any reference to attached, fixed, connected orthe like may include permanent, removable, temporary, partial, fulland/or any other possible attachment option. Additionally, any referenceto without contact (or similar phrases) may also include reduced contactor minimal contact. Surface shading lines may be used throughout thefigures to denote different parts or areas but not necessarily to denotethe same or different materials. In some cases, reference coordinatesmay be specific to each figure.

All ranges and ratio limits disclosed herein may be combined. It is tobe understood that unless specifically stated otherwise, references to“a,” “an,” and/or “the” may include one or more than one and thatreference to an item in the singular may also include the item in theplural.

In various embodiments, an energy attenuating mounting foot is disclosedfor interfacing with a track in an aircraft interior. The energyattenuating mounting foot may comprise a cavity or other cut out toallow for deformation in response to bearing load. Such deformation mayattenuate the load, thus improving the likelihood that the energyattenuating mounting foot will survive the load without separating. Inthat regard, the energy attenuating mounting foot may be exposed to aload, deform to a degree (reversibly or irreversibly), and tend tomaintain attached to the track. Moreover, in various embodiments, anenergy attenuating mounting foot may comprise one or more lobes that donot contact a portion of the track in the absence of a load but do comeinto contact with the track in response to a load. Such a feature maytend to evenly distribute load from an energy attenuating mounting footto a track, thus tending to reduce the concentration of load in one ormore localized areas of the energy attenuating mounting foot.

With reference now to FIG. 1, in accordance with various embodiments, anassembly 100 comprising cabin fixture 100, an energy attenuatingmounting foot 200 and a track 300 is shown. Cabin fixture 100 maycomprise an aircraft seat, table, cargo management device, or otheraircraft interior fixture. The dashed lines indicate a coupling betweenthe cabin fixture 100, the energy attenuating mounting foot 200 and thetrack 300. Xyz axes are shown for convenience, with z extendingperpendicular to the xy plane. In that regard, a measurement pointdisplaced in the positive z axis direction from a given reference pointmay be considered “above” or on “top” of the given reference point. Incontrast, a measurement point displaced in the negative z axis directionfrom the given reference point may be considered “below” or on “bottom”of the given reference point. In that regard, the terms “top” and“bottom” may refer to relative positions along the z axis. For example,cabin fixture 100 is on top of energy attenuating mounting foot 200,energy attenuating mounting foot 200 is on top of track 300, and track300 is below cabin fixture 100.

In various embodiments and with reference now to FIG. 2A, an energyattenuating mounting foot 200 may comprise load beam 202 having alongitudinal axis 203. Energy attenuating mounting foot 200 may furthercomprise top surface 206 configured to be coupled to a cabin fixturesuch as cabin fixture 100 and a bottom surface 204. In variousembodiments, the load beam 202 may have steps 208 cut from the load beamtop surface 206 and may feature threaded couplings 207 in top surface206. In various embodiments, a stud 222 configured to couple to a cabinfixture such as cabin fixture 100 may extend upward from the load beamtop surface 206. The stud 222 may be threaded to facilitate coupling theenergy attenuating mounting foot 200 to a cabin fixture such as cabinfixture 100. Energy attenuating mounting foot 200 comprises inner trackinterface lobes 214 a and outer track interface lobes 210 a and 210 bspaced along the longitudinal axis 203 and extending from laterally(along the x axis) side of the load beam 202.

In various embodiments and with reference now to FIGS. 2B, 2C, 2E and2F, an energy attenuating mounting foot 300 may comprise features sharedwith energy attenuating mounting foot 200, though energy attenuatingmounting foot 300 comprises inner track interface lobes 214 b, 216 a and216 b.

In various embodiments, an energy attenuating mounting foot may be madeof metal, an alloy, aluminum, aluminum alloy, titanium, titanium alloy,steel, a martensitic precipitation-hardening stainless steel such asthat sold commercially as both 17-4® stainless steel and/or 15-Ststainless steel. In various embodiments, an energy attenuating mountingfoot may be surface treated or heat treated. In various embodiments, themounting foot may be heat treated to H1025 and passivated per AMS-2700,Type 2, Class III protocol as set forth by SAE International. In variousembodiments, an energy attenuating mounting foot may have a materialgrain direction substantially parallel to its longitudinal axis such aslongitudinal axis 203.

In various embodiments and with reference now to FIG. 2C, apart from theload beam top surface 206 and step 208, inner track interface lobe 214 ahas a first surface 216 a and outer track interface lobe 216 a has asecond surface 212 a.

In various embodiments and with reference now to FIGS. 2B and 2D, achannel 218 is cut into the load beam bottom surface 204 alonglongitudinal axis 203 between the inner track interface lobe 214 a andinner track interface lobe 214 a, leaving a thickness of sidewall 220between the inner track interface lobes.

In various embodiments and with reference now to FIGS. 2E and 2F, thechannel 218 is cut a depth (along z axis) from the load beam bottomsurface 204 into the load beam 202 toward the load beam top surface 206,leaving a channel floor 224 with filleted edges 226. The first surface216 of inner 214 track interface lobe lies below the plane defined bythe second surface 212 of the outer 210 track interface lobe. Statedanother way, the first surface 216 is more proximate the bottom surface204 of the load beam than the second surface 212 is proximate the bottomsurface 204 of the load beam.

In various embodiments and with reference now to FIGS. 3A and 3B, anaircraft track 300 is shown. The aircraft track 300 has cutouts 302 toadmit the inner 214 and outer 210 track interface lobes of an energyattenuating mounting foot 200 and a mounting foot interface lobe 304 toengage a track interface lobe of the mounting foot. Track 300 has a topsurface 306 and a bottom surface 308 and an interior surface 310 of amounting foot interface lobe 304.

In various embodiments and with reference now to FIGS. 4A and 5A, anassembly 400 comprising energy attenuating mounting foot 200 disposedwithin track 300 is subjected to an upward force 402. The assembly 400resists the upward force by engagement of the inner interface lobes 214and outer interface lobes 210 against the mounting foot interface lobes304.

In various embodiments and with reference now to FIG. 4B, engagement ofthe lobes is achieved by inserting the energy attenuating mounting footinto the track and sliding it along the track as indicated by the dashedarrows. The inner interface lobes 214 and outer interface lobes 210lobes of the energy attenuating mounting foot 200 are inserted throughthe cutouts 302 of the track 300. Then, by sliding the energyattenuating mounting foot along track 300, the inner interface lobes 214and outer interface lobes 210 track interface lobes are brought to restunder the mounting foot interface lobes 304 of the track 300. In thisstate, absent upward force 402, inner interface lobes 214 do not contacttrack 300 but outer interface lobes 210 do contact track 300, and inparticular, mounting foot interface lobes 304. In response to upwardforce 402, interface lobes 214 may be displaced in the positive zdirection and contact mounting foot interface lobes 304.

In various embodiments and with reference now to FIG. 4C, the outer 210track interface lobes of the energy attenuating mounting foot 200 areengaged with mounting foot interface lobes of the track 300 when thesecond surface 212 of the outer interface lobes 210 is in contact withan interior surface 310 of the mounting foot interface lobe 304 and thebottom surface 204 of energy attenuating mounting foot 200 is proximatethe bottom surface 308 of the track 300.

In various embodiments and with reference now to FIG. 5B, the inner 214track interface lobes of the energy attenuating mounting foot 200 areengaged with mounting foot interface lobes of the track 300 when thefirst surface 216 of the inner interface lobe 214 lobe is separated froman interior surface 310 of the mounting foot interface lobe 304 by a gap500. Exposure to an upward force 402, for example a 16 G dynamic loadcause the load beam 202 of the energy attenuating mounting foot 200 toundergo plastic deformation, closing the gap 500 and bringing the firstsurface 216 of the inner track interface lobe 214 into contact with theinterior surface 310 of the mounting foot interface lobe 304. In variousembodiments the gap may be about 0.04 inches/1.02 mm or less, where theterm “about” in this context means+/−0.01 inches/0.0254 cm.

In various embodiments and with reference now to FIG. 6, a contour plotrepresenting the stresses in energy attenuating mounting foot 200mounted to track 300 and subjected to a load condition. Stressconcentrations 602 and 604 are still present in the energy attenuatingfoot 200 but much stress has been attenuated through migration into theload beam with large areas of concentration at 702 and 704 and thegreatest stresses at 706, evidencing deformation of the load beam 202.

In various embodiments and with reference now to FIG. 7, a contour plotrepresenting the stresses in a track 300 driven by the energyattenuating mounting foot 200 subjected to a 16 G load condition showsseveral stress concentrations at 902, 904, and 906 which have beenattenuated by the energy attenuating mounting foot to levels below thefailure point of the track material.

In various embodiments and with reference to FIG. 8, a method 800 ofmanufacturing an energy attenuating mounting foot may comprise forming aload beam 802 having a longitudinal axis, a top surface, a bottomsurface, and at least one inner track interface lobe and at least twoouter track interface lobes along the longitudinal axis of the load beamextending laterally from the load beam, Forming a channel 804 along thelong axis of the load beam in bottom surface of the load beam to a depthbetween the bottom surface and the top surface of the load beam. Forminga channel 804 may be accomplished by any of the techniques commonlyknown in the art such as end milling with a square end cutter or ballend cutter or the like. Altering a surface 806 of an inner trackinterface lobe such that the altered surface is disposed below a planedefined by an outer track interface lobe surface. Altering the surface806 of an inner track interface lobe may be accomplished by any of thetechniques commonly known in the art such as end milling, or by facemilling, or by grinding, or by ablation, or by electrical dischargemachining.

Benefits, other advantages, and solutions to problems have beendescribed herein with regard to specific embodiments. Furthermore, theconnecting lines shown in the various figures contained herein areintended to represent exemplary functional relationships and/or physicalcouplings between the various elements. It should be noted that manyalternative or additional functional relationships or physicalconnections may be present in a practical system. However, the benefits,advantages, solutions to problems, and any elements that may cause anybenefit, advantage, or solution to occur or become more pronounced arenot to be construed as critical, required, or essential features orelements of the disclosure. The scope of the disclosure is accordinglyto be limited by nothing other than the appended claims, in whichreference to an element in the singular is not intended to mean “one andonly one” unless explicitly so stated, but rather “one or more.”Moreover, where a phrase similar to “at least one of A, B, or C” is usedin the claims, it is intended that the phrase be interpreted to meanthat A alone may be present in an embodiment, B alone may be present inan embodiment, C alone may be present in an embodiment, or that anycombination of the elements A, B and C may be present in a singleembodiment; for example, A and B, A and C, B and C, or A and B and C.Different cross-hatching is used throughout the figures to denotedifferent parts but not necessarily to denote the same or differentmaterials.

Systems, methods and apparatus are provided herein. In the detaileddescription herein, references to “one embodiment”, “an embodiment”,“various embodiments”, etc., indicate that the embodiment described mayinclude a particular feature, structure, or characteristic, but everyembodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of oneskilled in the art to affect such feature, structure, or characteristicin connection with other embodiments whether or not explicitlydescribed. After reading the description, it will be apparent to oneskilled in the relevant art(s) how to implement the disclosure inalternative embodiments.

What is claimed is:
 1. An energy attenuating mounting foot comprising: aload beam having a longitudinal axis, a top surface, a bottom surface,an inner track interface lobe, and an outer track interface lobe, theinner track interface lobe and the outer track interface lobe extendinglaterally from the load beam, and a channel along the longitudinal axishaving a depth extending from the bottom surface toward the top surface,wherein the inner track interface lobe has a first length extending in afirst direction from the bottom surface towards the top surface and theouter track interface lobe has a second length extending in a seconddirection from the bottom surface towards the top surface, the firstlength being less than the second length.
 2. The energy attenuatingmounting foot of claim 1, wherein the inner track interface lobe and theinner track interface lobe are shaped to fit through an opening of atrack having a mounting foot interface lobe.
 3. The energy attenuatingmounting foot of claim 2, wherein the inner track interface lobe isseparated from the mounting foot interface lobe.
 4. The energyattenuating mounting foot of claim 2, wherein the inner track interfacelobe contacts the mounting foot interface lobe in response to a loadplaced on the load beam.
 5. The energy attenuating mounting foot ofclaim 1, wherein the channel extends along a portion of the longitudinalaxis.
 6. The energy attenuating mounting foot of claim 1, wherein theload beam comprises at least one of steel, aluminum, aluminum alloy,titanium, or titanium alloy.
 7. The energy attenuating mounting foot ofclaim 1, wherein the load beam comprises a martensiticprecipitation-hardening stainless steel.
 8. The energy attenuatingmounting foot of claim 6, wherein a material grain direction of the loadbeam substantially parallels the longitudinal axis.
 9. The energyattenuating mounting foot of claim 2, wherein the load beam undergoesplastic deformation across the channel in response to a load placed onthe load beam.
 10. The energy attenuating mounting foot of claim 1,wherein the load beam further comprises a stud.
 11. The energyattenuating mounting foot of claim 10, wherein the stud is coupled to acabin fixture.
 12. An energy attenuating mounting foot comprising: aload beam having a longitudinal axis, a top surface, a bottom surface, afirst inner track interface lobe, a second inner track interface lobe, afirst outer track interface lobe, and a second outer track interfacelobe, the first inner track interface lobe, the second inner trackinterface lobe, the first outer track interface lobe, and the secondouter track interface lobe extending laterally from the load beam,wherein the first inner track interface lobe, the second inner trackinterface lobe, the first outer track interface lobe, and the secondouter track interface lobe are displaced along the longitudinal axis;and a channel along the longitudinal axis terminating at the first innertrack interface lobe and the second inner track interface lobe, thechannel having a depth extending from the bottom surface toward the topsurface.
 13. The energy attenuating mounting foot of claim 12, whereinthe first inner track interface lobe and the second outer trackinterface lobe are shaped to fit through openings of a track having amounting foot interface lobe.
 14. The energy attenuating mounting footof claim 13, wherein the first inner track interface lobe is separatedfrom the mounting foot interface lobe.
 15. The energy attenuatingmounting foot of claim 14, wherein the first inner track interface lobeis configured to contact the mounting foot interface lobe in response todeformation of the load beam.
 16. The energy attenuating mounting footof claim 12, wherein the load beam comprises a stud.
 17. The energyattenuating mounting foot of claim 12, wherein the load beam comprisesat least one of steel, aluminum, aluminum alloy, titanium, or titaniumalloy.
 18. The energy attenuating mounting foot of claim 12, wherein theload beam comprises a martensitic precipitation-hardening stainlesssteel.
 19. The energy attenuating mounting foot of claim 12, wherein amaterial grain direction of the load beam substantially parallels thelongitudinal axis.
 20. A method of manufacturing an energy attenuatingmounting foot comprising: forming a load beam having a longitudinalaxis, a top surface, a bottom surface, an inner track interface lobe,and an outer track interface lobe disposed along the longitudinal axisof the load beam extending laterally from the load beam, forming achannel along the longitudinal axis of the load beam in the bottomsurface of the load beam to a depth between the bottom surface and thetop surface.